Mercerizing solutions

ABSTRACT

Aqueous mercerizing solutions containing an alkali metal hydroxide and an alkali metal salt of a phosphinic acid of the formula   in which R1 is methyl or ethyl and R2 is an aliphatic hydrocarbon radical of 4 to 12 carbon atoms, and the use of these solutions for mercerizing cellulosic fibrous materials.

United States Patent [1 1 Kleiner et a1.

1 1 MERCERIZING SOLUTIONS [73] Assignee: Hoechst Aktiengesellschaft,

Frankfurt am Main, Germany [22] Filed: June 21, 1973 [21] Appl. No.: 372,330

[30] Foreign Application Priority Data June 26, 1972 Germany 2231147 [52] U.S. Cl 8/127; 8/125 1 [58] Field of Search i. 8/116 P, 127, 125

[56] References Cited UNITED STATES PATENTS 1,980,342 11/1934 Kern 8/127 451 July 1, 1975 2,236,617 4/1941 Brandt 3/127 2,403,038 7/1946 Aelony 8/127 2,478,390 8/1949 Hanford et al 260/459 $325,654 4/1943 Volz 8/127 Primary ExaminerBenjamin R. Padgett Assistant Examiner-B. Hunt Attorney, Agent, or Firm-Connol1y and Hutz [57] ABSTRACT Aqueous mercerizing solutions containing an alkali metal hydroxide and an alkali metal salt of a phosphinic acid of the formula in which R, is methyl or ethyl and R is an aliphatic hydrocarbon radical of 4 to 12 carbon atoms, and the use of these solutions for mercerizing cellulosic fibrous materials.

4 Claims, 2 Drawing Figures SHEET 1 Shrinkage FIG. 1

7 5 9 0 sec EU n FIG. 2

Shrinkage Rate mm /sec MERCERIZING SOLUTIONS The present invention relates to aqueous solutions containing alkaline agents and phosphinic acids for mercerizing purposes.

For the purpose of mercerizing and treating cellulosic fibers, especially cotton fibers and goods made therefrom, with lyes, alkali metal hydroxide solutions having a strength sufficient to meet certain requirements are allowed to act on the material. To accelerate this operation thus assuring a continuous and economical working process, it is necessary to have the material soaked with alkaline solution as quickly and uniformly as possible. To this effect, wetting agents are added to the solutions while making sure that these are readily soluble in the lye, bring about a maximum shrinkage rate of the cellulosic fiber within the shortest possible time and remain in solution even after the lyes have been stored for a prolonged period of time.

It is already known that alkyl sulfates, alkane sulfonates, alkyl-aryl sulfonates, lignin sulfonic acids, sulfated terpene derivatives, alkylated naphthalene sulfonic acids and analogous compounds can be used as wetting agents in mercerizing liquors. German Auslegeschrift No. 1,014,067 discloses the application of mixtures of such mono and polysulfonic acids or salts thereof in mercerizing baths. Those compounds have been obtained by sulfo-chlorination of aliphatic or cycloaliphatic hydrocarbons having 10 to 20 carbon atoms.

The wetting agents are generally combined with other adjuvants which disperse and keep in suspension the products which have been dissolved off the fiber during the mercerizing operation, for example cellulose degradation compounds or remaining sizes. At the same time, these adjuvants have a synergistic effect on the wetting power of the wetting agents which are known to be low-molecular-weight alcohols, for example isopropanol, butanols, alkanol-amines, glycols and derivatives thereof, polyglycols and other compounds disclosed, inter alia, in Lindner Tenside, Textilhilfsmittel, Waschrohstoffe", vol. II, 1964, pages 1476 to 1478.

Wetting agents hitherto used for mercerizing liquors do not meet all the practical requirements at the same time. They either wet the fiber very rapidly while having to be used, however, in high concentrations or they are not stable in the alkaline solutions for a sufficiently long time, lose their effectiveness or precipitate. in many cases, moreover, their heavy foaming is troublesome.

This invention now relates to aqueous solutions for mercerizing and treating cellulosic fibers and goods made therefrom with lyes, which have an excellent wetting effect and a high stability and contain, in addition to about l to 400 g/l of sodium, potassium or lithium hydroxide or mixtures of these alkaline agents, as wetting agents, from 0.] to g/l of phosphinic acids of the general formula in which R, stands for a methyl or ethyl group and R for an aliphatic linear, branched or cyclic hydrocarbon radical having 4 to 12 carbon atoms, preferably 6 to 10 carbon atoms, in the form of their alkali metal salts as essential ingredients.

The phosphinic acids or the alkali metal salts thereof to be used as wetting agents according to the invention may be prepared according to various methods, for ex ample by the known reaction of sodium salt of methane-phosphonic acid monoethyl ester with Grignard compounds (cf. K. A. Petrov et, al., Z. obsc. Chim. 30 1964-8 (1960); C.A. 55, 6363b (l96l). The process disclosed in French Patent No. 7,045,l30 and German Offenlegungsschrift No. 2,l00,779 is especially preferred, according to which dialkyl phosphinic acid alkyl esters of the general formula R OR 0 ii f" a in which R and R are defined as above. As phosphonous acid alkyl esters suitable for this reaction, there are mentioned, for example, methane-phosphonous acid methyl ester, methanephosphonous acid ethyl ester, octane-phosphonous acid ethyl ester. The salts or free acids thereof may be prepared from the dialkyl phosphinic acid esters by hydrolysis according to known methods, advantageously by an alkaline saponi fication. The solutions of the invention may, however, also be prepared using the dialkyl phosphinic acid esters or the free acids. thereof.

The phosphinic acids and the salts thereof to be used according to the invention are readily soluble in water and give limpid solutions. In an alkaline medium, they have such an excellent wetting power that they can be used in lower amounts than conventional wetting agents. The concentrations used in the mercerizing solutions are between O.l and 5 g/l, which means not only a very economical application of the compounds but also hardly any pollution of waste water. Furthermore, the phosphinic acids and the salts thereof do practically not foam in the alkaline solutions. They are preferably used for mercerizing liquors containing a high amount of about to 300 g, preferably 200 to 250 g of sodium-, potassiumor lithium hydroxide or mixtures thereof per liter of liquor.

The known addition of lower alcohols, for example isopropanol or butanol, or of alkanol-amines, for example butyl-diethanol-amine, to the mercerizing solutions, may further improve the wetting power of the solutions.

The composition of the mercerizing solutions, for which the phosphinic acids or the salts thereof are used 3 4 according to the invention. is known; they generally Liquor No. I 1 0.3 g/) or methyl-octyl PlttiSPhifliL acid Contain l 9 g of Sodium putflssiunfik lithium Liquor No. 2 l :Il iil riiirhlil il ig'l i'lhtisphinic acid hydroxide or mixtures thereof per liter of liquor and. Liquurs N g/l o meth l-Ugl phusphinlc acid where required, further usual adjuvants. The solutions 4 7 s f are used at temperatures of from about 0 to 25C. As 5 Llqum NO 4 I phos fil'lii'lig jdlll to further additives, see Lindner Tenside. Textilhilfs- Liquor Na 5 1 all at n y li whusphiniv mittel, Waschrohstoffe", vol. ll. l9o4. pages 1476 to 1478, and Ullmanns Encyclopadie der technischen [)5 g/l orn-hutunol' Ch i 3 d di i L 17 9 6 pages 17 to 77 Liquor No. 6 1.5 g/l of paraffin polysulfonatc (from By the way, it is not necessary at any circumstances It) 1 'IE Z IFTF ij ii ii l i Plltll' tll' g l-U U} l\. d1 tll'l'llnk, to convert the dialkyl phosphinic acid esters prepared liquflri 8 vl'lrilmbulyl PhHSPhHIB and according to the prior art indicated above into the corresponding acids or alkali salts to use them according to the invention. It is also possible to add the esters di rectly to the merceri zing solutions. since they are hyl The good Stability of the phosphinic acids used dmlyzed m thlz.ulkullne.llquor to wield cording to the invention even in lyes having an ex- The mercenzmg Solutlons the mvelltlml are used tremely high concentration of alkalis is demonstrated in known manner for treating cellulosic fibers and by the: results Obtained with goods made therefrom as well as textile material containing cellulosic fibers in addition to synthetic fibers. 20

For further illustration. the values of shrinkage and Liquors Ni, 7 and 7 my. h i k t are given di mj fl b way f Liquors No. 7 and 7 la): 330 g/l of sodium hydroxide ample in the accompanying drawings. ornmhthml. HO. 1 shows the values of shrinkage as a function of Phmphinis 4 time using liquors Nos. 1, 5 and 6. 35

FIG. 2 shows the corresponding values of shrinkage Liquors Nos. 3 (u) and 7 (a) had the same composition rate as a function of time. as liquors Nos. 3 and 7 but had been allowed to stand The following Examples serve to illustrate the invenfor 24 hours prior to its use for the tests. tion. The test results are compiled in the following Table TABLE Time shrinkage in shrinkage rate sec. mm in mm/scc.

liquor number l I 3 3a 4 5 (l 7 7a 1 2 3 3a 4 (y 7 7 5 22 I3 58 57 3 47 4- I!) 2'. I3 58 57 3 47 4 25 Ill l0 74 50 92 88 36 90 l4 55 5t) 52 37 34 3l 33 43 H] 3t] 20 119 90 9s 9s 71 97 34 73 70 4s 6 lo 3s 7 2a is 2U 30 126 95 99 99 75 99 5| 76 7b 7 5 l l 4 2 l7 3 6 129 98 99 100 71-4 Hi] 64 7s 7s 1 3 o l 1 2 H 2 2 6O l3() )9 I00 lOU 8U I02 75 79 79 l l l U 2 I ll l l 75 130 I00 l0] l0] 81 I02 81) 79 79 U l l l 1 ll 5 U l 90 l33 lUl lill lUl 82 I03 84 Pill 80 Z l (I U l l 4 l l EXAMPLES The results convincingly demonstrate the advantage Since the wetting power of strongly alkaline liquors of the phosphmlc uclds the ,alkall Salts cannot be measured using conventional devices Ho thereof to be used according to the invention. The re. cording to German industrial Standards (DIN) 53 901. measurfid on llquors 3 and Show the following tests were carried out using. as a measure altered Wttmg power of the mercsenzmg Solutions of for the Wetting power of a mercerizmg liquor the the invention even after a storage tlme of 24 hours. shrinkage of cotton in this liquor. For this purpose, a we cla'm: I I test device suitable for measuring mercerizing liquors 5i f An aqueous mercenzmg Solunon essentially according to Hintzmann was used This device is de swung of about m to 400 g/l of 50dhlm- Potassium 0T scribed in detail in Mclliand Textilberichte" I968 lithium hydroxide Ur mixture hereof, and t0 5 E" No. 3. pages 3 ll to 3 l5 and No. 4. pages 450 to 456. of a PhUSPhihlC acid of the formula This device was operated at 20C with an amount of 250 cc. under a charge of 33 grams. Measuring was performed on cotton hanks (/2-fold) having a length 1 12;; of 27.4 cm. Shrinkage was measured after a period of action of the liquor of 5, 10.20. 30, 45. 60, and seconds. The shrinkage rate in mm/sec. was calculated from the shrinkage values obtained in mm. 65 in which Stands for a methyl or ethyl g p and 2 All the tested mercerizing liquors contained 220 g of sodium hydroxide per liter and. in addition. the following wetting agents and adjuvants:

stands for an aliphatic linear. branched or cyclic hydrocarbon radical having 4 to I 2 carbon atoms, in the form of its alkali metal salt.

2. An aqueous mercerizing solution as claimed in claim I having a content of U.l to 5 g/l of methyl-octyl phosphinic acid in the form of its alkali metal salt.

3. An aqueous mercerizing solution as claimed in claim 1 having a content of 0.1 to 5 g/l of mcthyl-hexyl phosphinic acid in the form of its alkali metal salt.

4. A process for treating with lyes and mcrccrizing cellulosic fibrous material which comprises treating the fibrous material with an aqueous alkaline mcrceriz ing solution essentially consisting of about l() to 400 g/l of sodium, potassium or lithium hydroxide and as a wetting agent Ol to 5 g/l of a phosphinic acid of the formula carbon atoms, in the form of its alkali salt. 

1. AN AQUEOUS MERCERIZING SOLUTION ESSENTIALLY CONSITING OF ABOUT 10 TO 400 G/L OF SODIU POTASSUM OR LITHIUM HYDROXIDE OR A MIXTURE THEREOF, AND 0.1 TO 5 G/L OF A PHOSPHINIC ACID OF THE FORMULA
 2. An aqueous mercerizing solution as claimed in claim 1 having a content of 0.1 to 5 g/l of methyl-octyl phosphinic acid in the form of its alkali metal salt.
 3. An aqueous mercerizing solution as claimed in claim 1 having a content of 0.1 to 5 g/l of methyl-hexyl phosphinic acid in the form of its alkali metal salt.
 4. A PROCESS FOR TREATING WITH LYES AND MERCERIZING CELLULOSIC FIBROUS MATERIAL, WHICH COMPRISES TREATING THE FIBROUS MATERIAL WITH AN AQUEOUS ALKALINE MERCERIZING SOLUTION ESSENTIALLY CONSISTING OF ABOUT 10 TO 400 G/L OF SODIUM, POTASSIUM OR LITHIUM HYDROXIDE AND AS A WETTING AGENT 0.1 TO 5 G/L OF A PHOSPHINIC ACID OF THE FORMULA 